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I haven't looked inside my inverter tig machine, but would not be surprised to see some electrolytic capacitors on control boards, particularly power supplies. Some e-caps go bad in 8-10 years, so perhaps, we have this to look forward to. I have brought TVs and VCRs back to life by replacing bad caps.

Inverter welders are more versatile than transformer welders but they have a weakness. Inverter welders have many, many more internal connections than transformer based welders and their components are more sensitive to sustained high temperatures. Time, temperature changes and use cycles have a tendency wreak havoc on inverter welders.

The only way to reduce the effect of these evils is to do what Cruizer suggested: keep the welder cool by blowing it out and (most important) periodically tighten the internal connections that loosen with heating/cooling (use cycles). It does not take much in the way of increased resistance to current flow, read this as connections not quite snug (remember, high amps require uninterrupted current pathways), to burn out internal components. The result of negligence can be very, very expensive.

Here is my 2 cents

and probably not worth that.
Owning a shop I look at the cost of equipment and what it can produce in the time it is alive.

If a $4000.00 machine lasts 12 years and can produce say 8 hours a day at lets say you get $50/hour. What is the value of the machine?

Go get another because you have set aside your $3/month for new equipment, haven't you?

Stop complaning, some of my equipment cost over $100K each and I have worked them 10 to 12 hours a day and 2 of them are 15years old. My hourly is higher than $50. My new equipment fund will buy replacements at this point for cash. If you prepare, do your maintainance, work the machines for profit, not just to get by you will be fine.

If you are a weekend warrior, you bought 1st quality gear, you should be smiling.

It is a basic truism in the (especially capitalistic) world that if you produce crap, you are likely to have your business fail or underperform badly.

Wondering aloud: Are WalMart and Harbor Freight exempt from this "basic truism?"

Back on topic:

The one type of component that that limits the life of modern electronic equipment is the electrolytic capacitor. By its very nature it contains an electrolyte that will, over time, leak and/or evaporate. Of course there are exceptions to every rule and there are a few Atwater-Kent radios with huge old electrolytic cans-- or the earlier cardboard tubes-- that may still work, although by far the majority died decades ago.

Modern electrolytics are even designed with a safety top that allows them to more safely leak/explode when they die. Not that long ago, millions of counterfeit Chinese electrolytics made there way into even high-end consumer electronics such as cellphones, auto modules, even Apple computers-- leading to a premature death at considerable cost to customers.

Electrolytic capacitors are even designed with a life expectancy-- usually measured in thousands of hours at a given maximum temperature. Heat is their enemy which explains why the life of inverter welders is shorter than old transformers. Open a modern inverter welder or plasma cutter, and you will find its boards packed with small electrolytic cans.

In addition to being run right up to their duty cycle when they automatically shut down to cool off, inverters often spend their working lives in garages exposed to extremes of hot and cold-- all of which ultimately kill electrolytics.

If science can someday design a device to replace electrolytics, such device possessing the stability of components such as resistors, transistors, diodes, inductors-- including transformers and chokes-- and microprocessors, you can expect the life of electronic equipment to increase exponentially.

However such a mass-produced device is still in the theoretic world of optical buses.

capacitor life

Previous posters are correct--heat and electrolytic caps will bound the life of any piece of electronic gear.

Don't electrolytics dislike sitting idle month after month? I recall (dimly) discussions about "reforming" stale caps, required after long periods of non-use. I believe the reforming procedure isn't a cure all, and I don't think it could be performed feasibly on the multitude of small electrolytics on a circuit board.

Obviously this isn't a problem for the professional welder, but might be for a hobbyist.

Maybe one of Miller's reliability engineers could weigh in: Would firing up an inverter welder at least, say, every month extend the capacitor life of an inverter device?

My Japanese OTC AVP300 amp inverter Tig machine is still going strong and it's got to be over 12 years old now.
It's an older style analogue machine which doesn't have some of the features the new machines have now but it still has the best AC balance control of any machine I've used.
Looking inside the machine to how it's made and it's 1st rate with everything neatly in place.
This is my daily workhorse and it gets used all the time and apart from cooking a couple a Tig torches it has done so much work it's paid for itself many times over.
There is no way I'd ever go back to a transformer machine, the characteristics of the inverter makes it superior in so many situations, particularly on the AC side.
Regards Andrew from Oz.

This was an issue with Variable Frequency Drives when they first started showing up in the industrys. You were counseled to power up the drive and let it sit idle for some hours to recondition the caps from storage. I haven't seen that admonition for many years but I still do it with any new install.

I doubt that there's been any significant improvement in Electrolytics over the years....

Originally Posted by jackw19

Previous posters are correct--heat and electrolytic caps will bound the life of any piece of electronic gear.

Don't electrolytics dislike sitting idle month after month? I recall (dimly) discussions about "reforming" stale caps, required after long periods of non-use. I believe the reforming procedure isn't a cure all, and I don't think it could be performed feasibly on the multitude of small electrolytics on a circuit board.

Obviously this isn't a problem for the professional welder, but might be for a hobbyist.

Maybe one of Miller's reliability engineers could weigh in: Would firing up an inverter welder at least, say, every month extend the capacitor life of an inverter device?